Advanced Remote Sensing

Analysis of the sea surface temperature (SST) of the Caspian Sea from NOAA satellites

2023-11-13T07:15:03+00:00

The sea surface temperature (SST) of the Caspian Sea as a whole is determined by air temperature, depth, that is, heat reserve, wind characteristics (mixing) and advection. In different regions of this continental sea, in addition to the connection with air temperature common to all regions, their own factors dominate. For the Northern Caspian, this is primarily the influence of river runoff - warm continental runoff in spring and cool in autumn. In the Middle Caspian, deep water rises near the eastern and western shores, reaching a temperature contrast near the eastern shore. In the Southern Caspian, this is winter wind mixing and advection of waters from the Middle Caspian. During the daytime, during the spring and summer months, the warming of the sea manifests itself everywhere in the form of areas of warm water with temperature contrasts in calm zones. In shallow water in the spring and autumn months, zones of heating and cooling are clearly visible, respectively, and the rate of heating and cooling is the higher, the shallower the depth of the sea, that is, the lower its heat reserve. The paper analyzes the available modern methods and means for determining the surface water temperature of the Caspian Sea. For their detection, data obtained by NOAA satellites and the AVHRR Pathfinder instrument (high-resolution radiometer) installed on them are used. In addition, the main regularities in the atmosphere-sea system are revealed according to the average annual values of their changes over a long period.

Assessing the impact of drought on groundwater resources using geospatial techniques in Balochistan Province, Pakistan

2023-04-02T12:39:57+00:00

Globally, drought is one of the hydro-meteorological disasters causing human loss, decrease in agricultural production, loss of soil moisture and ground water table. Drought has been particularly severe in Balochistan. The ground water table has been depleted as a result of the decrease in rainfall, which has severely damaged water in tube wells and springs. The purpose of current study is to analyze the impact of drought on groundwater in Balochistan by using geospatial technique approach. Data is acquired through questionnaire, focus group discussion and Global positioning system (GPS). The Analysis reveals that drought has physical, economic and environmental impacts, the decline in groundwater level, the drying up of well, reservoirs, lakes and springs were terribly observed in Balochistan. Devastating drought has demolished historical fruit like apricots which were being cultivated for last 30 to 40 years. The continuous usage of solar energy modules has severely reduced the ground water level. Consequently, obvious changes have been observed in groundwater table for 20 years. The water table has reached 320 feet where it was noted 160 in 2000. Likely, it would further decline with each passing day. Water is extremely declining even though in some areas the extraction level has touched 1400 feet. Meanwhile, few areas had no availability of clean drinking water. The government should emphasize the importance of PDMA organization cooperation and the development of a strategy to help all districts in improving and solidifying their drought policies.

Comparative character and monitoring of some parameters of the soil and vegetation by remote sensing in the zone of Zangilan

2023-11-20T07:02:56+00:00

It is important to reveal a character, scale and development line of the change in order to determine a potential and future enlargement direction of ecosystem. The monitoring of the changes occurring in some parameters of soil and vegetation in the research zone by GIS has been performed and the consequences have been compared in the article. It was determined that the positive tendency was shown in some parameters of soil and vegetation, but negative tendency was shown in some parameters. An investigation of the changes by the remote sensing were given on the basis of different parameters (NDVI, LST, VHI) using the satellite images (Landsat 5 TM; Landsat 8 OLI) in the research zone. Change of the area of forest ecosystem under the negative and anthropogenic influences were compared on different years (1990-2022 years). It was determined that an area of the optimally developed forests decreased 84.5 % (10.838.05 h). At present the serious degradation has occurred in a negative direction of the available forest area. The Sentinel-2 satellite images have been used to evaluate changes occurring in soil use/ soil cover (LU/LC) in the active war phase (2016-2022 years). The soils of the plain and foothill regions in the district have been subjected to all the types of degradation (physical, chemical, biological) as a result of the military-technogenic effect.

Importance of using GIS software in the process of application of Analogue terrains and Counter-approach technologies in water resources assessment

2023-11-20T06:54:02+00:00

The research is devoted to the wider application of GIS technologies in hydrological studies, especially in the assessment of water resources of rivers. Runoff formation is a very complex process that occurs under the influence of multiple factors. Studies show that the more flow-forming factors that are considered in the assessment process, the more accurate and reliable the results are. The practice of studying water resources based on the analogy of observed and unobserved river basins is a widespread approach in hydrology. Previously, analogies created on the basis of one or several predictors did not allow to obtain reliable results in the selection of analogue terrains. Modern scientific innovations have enabled more detailed analysis and modeling of runoff-forming processes. With our proposed method, analog geo-spaces are selected based on the similarity of most components through space information, and assessment is performed using GIS and other multifunctional technologies. Another advantage of the assessment with the new method is the ability to easily restore climate and runoff data for unobserved and extreme regions. Thus, on the basis of basins with hydrometeorological data, it is possible to estimate the water resources of any other unstudied rivers with high accuracy without time-space restrictions. Comparison of the actual and calculated by the proposed method of runoff for most of the river basins of Azerbaijan shows that the error between them was up to 10% in 92 cases out of 100.

Using GlobeLand30 data and cellular automata modeling to predict urban expansion and sprawl in Kigali City

2024-02-27T13:12:34+00:00

The growth and expansion of urban regions in various cities worldwide, especially in developing economies, leads to changes in land usage. Thus, the study assessed the changes in land use and land cover within Kigali City using the Land Change Modeler of the TerrSet software system. The study focused on 2010 to 2020, using classified GlobeLand30 maps to identify significant land cover transitions, which were then classified into submodels. An enhanced multi-layer perceptron neural network was also used to analyze these transitions. Urban expansion was predicted using five key variables: elevation, slope, distance from rivers, roads, and built-up areas. The multi-layer perceptron neural network achieved an accuracy of 81.90% in predicting land use and land cover changes. The Cellular Automata-Markov chain model in the Land Change Modeler was implemented to forecast land use and land cover patterns for 2030. Results indicated that (1) over the past decade (2010-2020), urban areas expanded by 20.89 km², while forests, grasslands, shrublands, and wetlands decreased by 1.31 km², 8.63 km², 0.15 km², and 0.05 km², respectively. The study also predicts that (2) from 2020 to 2030, urban areas and artificial surfaces will expand by 15.83%, with a considerable decrease in grassland and cultivated land. The study further predicts a slight decrease in wetland areas and for land use and land cover in Kigali City, highlighting the expansion of urban areas and their potential impact on other land uses. It serves as a critical tool to support sustainable urban planning and policies aimed at ensuring the long-term ecological and environmental sustainability of Kigali City.